After having reviewed the literature in the first part of this paper, we now present 6 selected cases to confirm the malignant potential of oral lichen planus (OLP), illustrating their particularities. Malignant transformation probably favored by chronic inflammation present in OLP is considered to arise in a small percentage in late stages (such as atrophic OLP or post-lichen state), but the true prevalence is probably underestimated because these lesions are often considered to be leukoplakia. Clinically malignant transformation will present as multiple lesions (verrucous carcinoma or squamous cell carcinoma), more or less spaced in time and often preceded by OIN (oral intraepithelial neoplasia). [ABSTRACT FROM AUTHOR]